Year	current US$
2000	33.53469698
2001	34.25621688
2002	37.35012419
2003	40.60569073
2004	44.94321412
2005	49.12800179
2006	53.58067023
2007	60.11089095
2008	74.24626156
2009	83.46729577
2010	90.83202095
2011	110.77227004
2012	126.13305512
2013	141.45714614
2014	150.84610104
2015	156.76530814
2016	167.08052905
2017	190.89030258
2018	220.00653278
2019	237.54207905
2020	264.15376679
2021	307.9776151